Image Empties: Option to not display the backside of image empties

Reviewers: brecht

Differential Revision: https://developer.blender.org/D3964

2 files changed, 23 insertions, 1 deletions

diff --git a/source/blender/blenkernel/BKE_object.h b/source/blender/blenkernel/BKE_object.h
index 6d950ec01f6..2527b0f5092 100644
--- a/source/blender/blenkernel/BKE_object.h
+++ b/source/blender/blenkernel/BKE_object.h
@@ -53,6 +53,7 @@ struct RigidBodyWorld;
 struct HookModifierData;
 struct ModifierData;
 struct HookGpencilModifierData;
+struct RegionView3D;
 
 #include "DNA_object_enums.h"
 
@@ -342,6 +343,8 @@ bool BKE_object_modifier_update_subframe(
         struct Depsgraph *depsgraph, struct Scene *scene, struct Object *ob,
         bool update_mesh, int parent_recursion, float frame, int type);
 
+bool BKE_image_empty_visible_in_view3d(const struct Object *ob, const struct RegionView3D *rv3d);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/source/blender/blenkernel/intern/object.c b/source/blender/blenkernel/intern/object.c
index d36a5838630..6590768917a 100644
--- a/source/blender/blenkernel/intern/object.c
+++ b/source/blender/blenkernel/intern/object.c
@@ -835,7 +835,8 @@ void BKE_object_init(Object *ob)
 	ob->empty_image_depth = OB_EMPTY_IMAGE_DEPTH_DEFAULT;
 	ob->empty_image_visibility_flag = (
 	        OB_EMPTY_IMAGE_VISIBLE_PERSPECTIVE |
-	        OB_EMPTY_IMAGE_VISIBLE_ORTHOGRAPHIC);
+	        OB_EMPTY_IMAGE_VISIBLE_ORTHOGRAPHIC |
+	        OB_EMPTY_IMAGE_VISIBLE_BACKSIDE);
 	if (ob->type == OB_EMPTY) {
 		copy_v2_fl(ob->ima_ofs, -0.5f);
 	}
@@ -4079,3 +4080,21 @@ bool BKE_object_modifier_update_subframe(
 
 	return false;
 }
+
+bool BKE_image_empty_visible_in_view3d(const Object *ob, const RegionView3D *rv3d)
+{
+	int visibility_flag = ob->empty_image_visibility_flag;
+
+	if ((visibility_flag & OB_EMPTY_IMAGE_VISIBLE_BACKSIDE) == 0) {
+		if (dot_v3v3((float *)&ob->obmat[2], (float *)&rv3d->viewinv[2]) < 0.0f) {
+			return false;
+		}
+	}
+
+	if (rv3d->is_persp) {
+		return visibility_flag & OB_EMPTY_IMAGE_VISIBLE_PERSPECTIVE;
+	}
+	else {
+		return visibility_flag & OB_EMPTY_IMAGE_VISIBLE_ORTHOGRAPHIC;
+	}
+}
\ No newline at end of file